Rendering of Pennsylvania Ave. with 200-foot buildings. Courtesy of DC Office of Planning.

This week is going to be a big one for the future of the Height Act that limits how tall DC’s skyline can go. Supporters of the 103-year-old law bashed the District government’s proposal to make significant changes at a DC Council hearing today. The National Capital Planning Commission is holding a meeting Wednesday where more of the public will be able to offer their input.

DC’s low skyline preserves clear sightlines of the US Capitol and Washington Monument, but city planners say the District is running out of room to accommodate a growing, economically diverse population.

“What kind of city do we want to be?” Harriett Tregoning, DC’s planning director, told Council members. Tregoning’s office published a lengthy study of the Height Act last month that was ordered up by House Oversight Chairman Darrell Issa, the District’s boss in Congress.

As written, the Height Act mandates that buildings in DC cannot be taller than the streets they front are wide. (In commercial zones buildings can go 20 feet higher.) Building heights top out at 160 feet along Pennsylvania Avenue. Tregoning’s proposal recommends letting structures go as high as 1.25 times the width of their streets within what planners refer to as “L’Enfant City,” the part of town south of Florida Avenue sketched out by Washington’s original master planner.

Throughout the rest of the city, Tregoning recommends removing the height limits, but only in certain areas where population growth is expected to be the most explosive. In total, she says her proposal affects 4.9 percent of the city’s land.

But that was too much for the historic preservation advocates and longtime denizens who followed Tregoning’s testimony today. “The low profile of the city’s skyline is an important element of maintaining the original vision for our city,” said William Brown, the head of the Association of the Oldest Inhabitants of the District of Columbia, a club for people over 40 who have lived here at least 20 years.

The Committee of 100 on the Federal City, a group that promotes unflinching adherence to the L’Enfant Plan, also sent over several witnesses. Height Act fans called Tregoning’s recommendations “radical” and “catastrophic.” But Tregoning repeated her earlier warnings about why the law should be altered—DC continues to take on more residents, pushing up housing prices and making it more expensive to live here.

Tregoning’s plan will likely take more whacks at the NCPC meeting on Wednesday. Her report will be presented against one composed by the commission which recommends leaving the Height Act almost entirely unchanged.

Benjamin Freed joined Washingtonian in August 2013 and covers politics, business, and media. He was previously the editor of DCist and has also written for Washington City Paper, the New York Times, the New Republic, Slate, and BuzzFeed. He lives in Adams Morgan.